This invention relates to a tone data recording and reproducing device which allows tone data such as waveform data to be recorded into and reproduced from a mass storage device such as a hard disk device.
Mass storage devices such as a hard disk device are commonly employed for recording tone waveform data that are sampled from the outside through a microphone or the like. In such a case, read/write operation of the hard disk is entirely managed or controlled by a general purpose control device like a personal computer. Namely, address management for data written into or read from the hard disk is entirely done by the personal computer program, and operations to record and reproduce tone waveform data are entirely controlled by the personal computer program.
In a reproduction process, for example, waveform data rapidly read out from the hard disk device are temporarily written into a buffer RAM (hereinafter, the term "RAM" represents a random access memory), and individual write addresses to write to the buffer RAM are also prepared by means of the personal computer program. The waveform data thus temporarily written into the buffer RAM are then read out in accordance with predetermined reproduction sampling clock pulse so as to reproduce sounds.
The above-mentioned prior art is however disadvantageous in that, since record and reproduction of the waveform data to and from the hard disk are entirely performed by the general purpose control device, i.e., personal computer, the personal computer is excessively bound by such record and reproduction processes, which very often presents a serious obstacle when it performs other processes in parallel with the record and reproduction processes. In the reproduction process, particularly, it is preferable to be able to not only reproduce sounds but also perform, in parallel therewith, various other additional functions such as a sequencer automatic performance function or a computer graphic function associated with a music piece performed. But, if the personal computer is bound by the record and reproduction of the waveform data to and from the hard disk, it becomes difficult or impossible for the personal computer to execute such an additional function in parallel with the record and reproduction processes. In order to eliminate the disadvantage, the computer must be substantially expanded in scale, or new programs permitting the required parallel execution must be developed.
Further, with the prior art technique, because arrangements are made such that the waveform data rapidly read out from the hard disk device are merely temporarily stored into the buffer RAM so as to allow the data to be read out in accordance with the predetermined reproduction sampling clock pulse, recorded contents in the hard disk device are wholly transferred to the buffer RAM and directly read out therefrom. Therefore, specific processes must be done in order to read out the waveform data transferred to and stored into a certain address range of the buffer RAM in accordance with the predetermined reproduction sampling clock pulse, thus requiring troublesome management of read addresses etc. Furthermore, up to now, any technique has not been proposed or considered which is adapted to properly dealing with special processes, such as process for simultaneously reproducing different waveform data through plural channels or a process for simultaneously reproducing data in which waveform data of plural channels are interleaved.
Furthermore, in the prior art, waveform data (audio data) to be successively generated in a data file are stored successively so that the waveform data are read out in a successive manner to reproduce sounds. It may be considered that automatic performance data represented in MIDI format are stored in the same data file as the waveform data in such a manner that the automatic performance data can be performed along with the waveform data of the data file, but it is customary that the MIDI data are all stored together in the head portion of the data file. In such a case, the MIDI data read out from the data file are stored into a buffer RAM, so that, when reading the waveform data, the MIDI data are read out in parallel with the waveform data to thereby generate automatic performance sequence sound. However, if, in this case, the waveform data stored in the data file are ones requiring a relatively long reproduction time, the MIDI data must also cover the long reproduction time, and hence an considerably large amount of the MIDI data must be stored in the buffer RAM. Accordingly, the buffer RAM of a large capacity is required.
The IEEE Journal published in 1981 contains a treatise "Delayed Playback Music Synthesis Using Small Computers" written by Hal Chamberlin, which discloses the use of floppy disk storage for recording and reproducing audio data. But, it does not disclose any solution to the above-mentioned problems.